Amperometric immunosensor for the detection of anti-West Nile virus IgG using a photoactive copolymer

A polymeric film consisting of two distinct monomers such as pyrrole–benzophenone and tris(bipyridine pyrrole) ruthenium (II) units was electrogenerated and used for the photochemical grafting of T7 bacteriophages displaying a specific West Nile virus (WNV) epitope. The resulting electrodes were applied to the amperometric detection of WNV antibody at 0 V in aqueous electrolyte via secondary peroxidase-labeled antibody, hydrogen peroxide and hydroquinone as the enzyme substrate. A calibration curve based on different WNV–antibody dilutions ranging from 10 to 106 was created with a relatively short response time of 30 s after substrate injection.